I got my 5404 going tonight on my Greyborg. I took it out for a quick spin. It pulls hard and has that nice smooth ride I find my 5303 used to have, and it definately pulls like a train. But unfortunately before I could get anything like a top speed or anything to report, I suddenly had a failure. Unfortunately I suspect one of two things, it is either a blown hall (please baby jesus don't be that), or else I may have slightly crushed and shorted the phase wires into each other enough to get an intermittend short, where they exit the axle. The way the wires exit the axle is ridiculous, and when I look down at it I can see that when I tightened my nuts, wires look quite a bit compressed inside the stupid little plastic thingy that covers them. But it is late tonight, and a mate of mine has borrowed my ebike tester so I won't know until tomorrow what my fate is. I am praying it is not a blown hall as I have still to succesfully replace the halls in my 5303 despite four failed attempts.
But here is a quick mobile phone photo of it in all its monstrous ludicrousness. The silver of it is giving a reflection of the flash, I think I will paint it black when I troubleshoot the problem. It weighs the same as a small house.
There is definately some QC issues on the build quality, for example two of my disc brake mount holes were not tapped properly, so that the screws don't go in. And as I said, my tip to punters yet to install theirs is to be really really careful about the plastic plug that the wires exit through, and making sure that you don't crush the wires inside it.